Live-streamed shopping has rapidly become a dominant retail format on digital marketplaces, merging real-time video broadcasting, social interaction, and instant transaction functionality within a single interface. This study analyzes the effectiveness of live-streamed shopping in shaping consumers’ impulsive buying behavior on marketplace platforms, using the Stimulus-Organism-Response (S-O-R) framework as the guiding theoretical lens. Employing a quantitative research design, this study develops a conceptual model in which live-streaming stimuli including streamer credibility, interactivity, social presence, visual appeal, and promotional cues such as scarcity and price discounts influence consumers’ internal organismic states (arousal, trust, perceived enjoyment, and urge to buy impulsively), which subsequently drive impulsive buying behavior. The study synthesizes findings from twenty-five peer-reviewed empirical studies published between 2021 and 2026 to formulate hypotheses intended for testing through a structured survey administered to active marketplace live-streaming shoppers, analyzed using Structural Equation Modeling. The synthesis indicates consistent empirical support for the mediating role of the urge to buy impulsively between live-streaming stimuli and actual purchase behavior, while contextual factors including time scarcity, product type, and consumer vulnerability moderate this relationship. This study contributes theoretically by extending the S-O-R framework into the marketplace live-streaming context and offers novelty by integrating consumer vulnerability and platform-based social presence as combined predictors, an area still underexplored in the Southeast Asian and Indonesian marketplace context. Practical implications for marketplace sellers and platform design are discussed.